Sonic protector for ears



March 12, 1957 J. LADD 2,784,407

soNIc PROTECTOR FoR EARs Filed oct. s1, 1955 l Y INVENTOR. F/5-/ United States Patent O SONIC PROTECTOR FR EARS John Ladd, Lynn, Mass. Application October 31, .1955, SerialNo.l 543,685

3 Claims. -(Cl.-23)

The present invention relates to Va device: for protecting an individuals hearing ability from injury dueto excessively.l loud sounds.

In various industries, yworkers are -subject `to noise levels which -are :much in @excess-#of the lninety -fdecibels .generally consideredto bethersafetyimaximumlforhuman longed. periods, decibel ratings in excess of 90f-decibels .will cause headaches, lextreme vear -pains and mental fatigue.

It is an object, therefore, of the present invention to Y overcome these bjectionble working conditions by providing an ear protect-ingdevicefwhihiis adapted to reduce the noise level considerably, whileaat thegaametime permitting normal conversation, shop noises, safety noises and other desirable sounds to be heard by the wearer of the present invention with little distortion. The present invention is not designed to eliminate completely all sounds at all frequencies. It does, however, reduce or flatten the harmful sound amplitudes to a reasonable level with the higher frequency sounds being more greatly affected than the lower frequency sounds. Speech may be clearly understood by a wearer of the present invention, although the words are slightly muilled.

It is further an object of the present invention to provide a protective device for the ear which reduces considerably the noise levels heard by the individual, but is light in weight and causes no discomfort to the wearer. The present invention also provides a structure in which no portion of the protective device is actually inserted into the ear canal, thus avoiding possible injury to the eardrum and inner ear.

A further object of the present invention is to provide a protective device for reducing noise levels heard by individuals by a percentage range of up to approximately 90%.

Further objects of the present invention provide ear protection devices which are readily adapted for use with protective helmets and which may readily be adjusted to cover the wearers ears.

One more object of the present inventionis to provide a light weight ear-protecting device which is quite comfortable to wear and which is both medically safe and easy to remove from the individuals head.

These and other objects of the present invention may be clearly understood when considered in connection with the accompanying drawings in which:

Figure 1 shows a front elevation of the invention as it is worn on the head of an individual;

Figure 2 illustrates a cross-sectional fragmentary view of the invention; and

have a thickness somewhat ICC Figure 3 illustrates a fragmentary view of a modification of the invention as used in connection with a protective helmet.

Referring specifically to the drawings of Figures 1 and 2, there isiillustrated -avprotective device madein accordance with the present invention in -which each ear-is covered by a shell-likeelement or ear covering generally designated a. These shell elements are open at their wide end or bottom and have ,a bottom opening of sufficient diameter to cover thefin'dividual .wearers ear. About the periphery of this `open bottom ofthe shells '1 is positioned a soft yielding resilient covering Aor.padding member generally designated 2. These sets of shellllike elements 1 are connectedtogether by two..s1idablehead band structures ,generally designated 3 .and 4.

The structureof each ear coveringl is more specifically illustrated in'Figure 2. I'In this'gure,.each coveringris shaped preferablyin.afrustoconical form and` is formed kof two shell members 5 and 6, concentric .withone another. 'Eachof these .conical forms are .provi'de'd with outwardly extending peripheral flange elements 7l and 18 respectively at'thebase. ThellangeS extendslbeyond the vflange 7` and'is spaceda short distancefrom it. jThese Yconical `members'S and`6 .are spaced .apart Afrom one vanother, providing an insulating'an section 9. "Theshells are ,held in this spaced'relation'bythe resilientlypadding (21) which is preferably formed of .a foam rubber material in an elongated sleeve. '.'Oneend 110.01 this sleeve is securedibetween the shellsLS .an'd6a short @distance down into the space 9 ,forming .the insulation. lThe padding 12 extends voutwardly from 'between the two llanges "7 and "S where it. is secured and Atightly .,held. *The other endjoffthisgan'nular*sleeve is reversely. bent in the jmanner .as indicated. .:As th is foam `rubber Vshould greater than the air space 9 and the width of the flange 7, it will extend inwardly and cover a substantial portion of the flange 7. The extreme outer end of this element 2 is bent downwardly over the flange 8 onto the -outside of the shell-like structure 1.

At the narrow end of this conical structure are secured the two slidable bands 3 and 4. These bands 3 and 4 are of conventional structure and may be made of elongated bands of metal, with each band 3 and 4 being divided into two overlapping sections 11 and 12. These bands 11 and 12 are held together, in longitudinal alignment for sliding upon one another to extend the elements 3 and 4 to various lengths, by the clip members 13 and 14, with clip member 13 fixed at one side to the band 11 and slidably encircling the band 12. Clip 14 is fixed securely to band 12 and slidably encircles band 11. The end of these structures 3 and 4 are secured to the shelllike member 2 by means of a bolt 15 which projects through the cones 5 and 6 and is secured in place by a nut 16. On the outside of cone 6 spacing locknuts 17 and 18 may be provided between the ends of elements 3 and 4 through which the bolt 15 passes. A gasket element 19 may also be provided on the bolt between the element 4 and the surface of the shell 6. In order to minimize the amount of noise, particularly low frequency noises passing through the shells 5 and 6, through the conduction of bolt 15, a tubular rubber-like covering 20 may be provided over the bolt 15. This tubular covering 20 is removable to allow the bolt itself to be removed.

The purpose of providing a removable nut and bolt structure 15 and 16 is to permit a ready servicing and replacement of the elements. If, however, a device is desired in which the dismountable feature of the present invention is not desired, the bolt 15 and nut 16 could be replaced by suitable rivet attaching means which would alsosecure the ends of the bands 3 and 4 in place.

This device as illustrated in Figures l and 2 is provided with a pair of bands 3 and 4 so as to permit the individual operator to adjust the protective devices over his ears in a manner individually suited to the wearer. These bands also per-mit a more certain gripping action of this device on the individuals head. This is quite important in many places where this device is used because the individual is subject at many times to sudden shocks and movement, such as are generated by dynamite blasts and riveting or the use of penumatic hammers. Thus, the bands 3 and 4 may be slightly separated as in Figure 1, providing an additional gripping contact with the wearers head.

Thepresent invention may also be adapted for use with protective helmets, such as are used by sand hogs inthe digging of underground tunnels. This modification is illustrated in Figure 3 in which 21 represents a protective helmet and 30 represents a shell member substantially similar to shell covering 1 of Figure 2, On the inner surface of this protective helmet there is provided a channel-like member 22 having essentially a U-shaped cross section with the longitudinal ends of the U attached to the sides of the helmet 21. Within this channel 22 is positioned a band 23 which terminates at its upper end in a T-shaped enlarged end 24. rI`his band 23 is free to move up and down in the channel 22 carrying the shell covering 30 with it, but is retained from moving out of the channel the corners of this channel 22 which are peened inwardly at 25 and 26 so that the enlarged end 24 will be stopped at the ends of the channel 22. Thus, an individual wearing this protective helmet may have the helmet moved in many directions or may tilt it for individual adjustment while the protective ear covering remains in the same desired position over the ear.

Having now described my invention, I claim:

1. A device adapted to lit over and protect the human ear from loud noises comprising concentric and spaced apart inner and outer shells made of acousticallyabsorbent material, outwardly-extending annular periph- `eral flanges secured to the edges of the shells with the ange on the inner shell disposed beyond and terminating radially inward from the liange of the outer shell, and an elongated annular sleeve made of resilient material extending from between the peripheries of the shells outwardly between the flanges, back over the outer surface of the flange on the inner shell and out over the outer surface of the flange on the outer shell.

2. A device of the character described comprising spaced apart and concentric frusto-conical inner and outer members made of sound insulating material and each having outwardly-extending flanges integral with their bases, said members defining an insulating air space between them, the liange of the outer member extending radially outward beyond the outer edge of the other flange, a sleeve made of sound insulating material having one end disposed between the members and extending about the outer edge of the flange of the outer member and back over the flange and to the outside of the outer member.

3. A device as defined in claim 2 further characterized by a bolt extending through the narrow ends of the members, and a sound insulating member covering the end of the bolt Within the inner member and engaging the inside of the inner member.

References Cited in the tile of this patent UNITED STATES PATENTS 261,196 Balch July 18, 1882 490,364 Rose Jan. 24, 1893 882,684 Hirsh et a1. Mar. 24, 1908 883,818 Lewis Apr. 7, 1908 1,456,524 Waldron May 29, 1923 2,476,589 Driskill July 19, 1949 2,532,852 Oaks Dec. 5, 1950 FOREIGN PATENTS 452,623 France Mar. 11, 1913 

